Instability of eating disorder diagnoses: prospective study.

BACKGROUND The stability of eating disorder diagnoses has received little research attention. AIMS To examine the course of the full range of clinical eating disorders. METHOD A sample of 192 women with a current DSM-IV eating disorder (55 with anorexia nervosa,108 with bulimia nervosa and 29 with eating disorder not otherwise specified) were assessed three times over 30 months using a standardised interview. RESULTS Although the overarching category of "eating disorder" was relatively stable, the stability of the three specific eating disorder diagnoses was low, with just a third of participants retaining their original diagnosis. This was due only in part to remission since the remission rate was low across all three diagnoses. CONCLUSIONS There is considerable diagnostic flux within the eating disorders but a low overall remission rate. This suggests that underpinning their psychopathology may be common biological and psychological causal and maintaining processes.